[U-Boot] [PATCH v5 03/14] mmc: sti_sdhci: Use reset framework

[Patrice CHOTARD]

Hi Simon

On 05/17/2017 03:38 AM, Simon Glass wrote:
> Hi Patrice,
>
> On 15 May 2017 at 03:21, Patrice CHOTARD <patrice.chotard at st.com> wrote:
>> Hi Simon
>>
>> On 05/15/2017 05:02 AM, Simon Glass wrote:
>>> Hi Patrice,
>>>
>>> On 10 May 2017 at 10:09,  <patrice.chotard at st.com> wrote:
>>>> From: Patrice Chotard <patrice.chotard at st.com>
>>>>
>>>> Signed-off-by: Patrice Chotard <patrice.chotard at st.com>
>>>> Reviewed-by: Jaehoon Chung <jh80.chung at samsung.com>
>>>> ---
>>>>
>>>> v5:     _ none
>>>> v4:     _ none
>>>> v3:     _ none
>>>> v2:     _ none
>>>>
>>>>
>>>>  drivers/mmc/sti_sdhci.c | 31 ++++++++++++++++++++++---------
>>>>  1 file changed, 22 insertions(+), 9 deletions(-)
>>>>
>>>
>>> Reviewed-by: Simon Glass <sjg at chromium.org>
>>>
>>> This is fine as is. But please see questions below.
>>>
>>>> diff --git a/drivers/mmc/sti_sdhci.c b/drivers/mmc/sti_sdhci.c
>>>> index d6c4d67..8b1b2c0 100644
>>>> --- a/drivers/mmc/sti_sdhci.c
>>>> +++ b/drivers/mmc/sti_sdhci.c
>>>> @@ -8,6 +8,7 @@
>>>>  #include <common.h>
>>>>  #include <dm.h>
>>>>  #include <mmc.h>
>>>> +#include <reset-uclass.h>
>>>>  #include <sdhci.h>
>>>>  #include <asm/arch/sdhci.h>
>>>>
>>>> @@ -16,6 +17,7 @@ DECLARE_GLOBAL_DATA_PTR;
>>>>  struct sti_sdhci_plat {
>>>>         struct mmc_config cfg;
>>>>         struct mmc mmc;
>>>> +       struct reset_ctl reset;
>>>>         int instance;
>>>>  };
>>>>
>>>> @@ -37,17 +39,19 @@ struct sti_sdhci_plat {
>>>>   * W/o these settings the SDHCI could configure and use the embedded controller
>>>>   * with limited features.
>>>>   */
>>>> -static void sti_mmc_core_config(struct udevice *dev)
>>>> +static int sti_mmc_core_config(struct udevice *dev)
>>>>  {
>>>>         struct sti_sdhci_plat *plat = dev_get_platdata(dev);
>>>>         struct sdhci_host *host = dev_get_priv(dev);
>>>> -       unsigned long *sysconf;
>>>> +       int ret;
>>>>
>>>>         /* only MMC1 has a reset line */
>>>>         if (plat->instance) {
>>>> -               sysconf = (unsigned long *)(STIH410_SYSCONF5_BASE +
>>>> -                         ST_MMC_CCONFIG_REG_5);
>>>> -               generic_set_bit(SYSCONF_MMC1_ENABLE_BIT, sysconf);
>>>> +               ret = reset_deassert(&plat->reset);
>>>> +               if (ret < 0) {
>>>> +                       error("MMC1 deassert failed: %d", ret);
>>>> +                       return ret;
>>>> +               }
>>>>         }
>>>>
>>>>         writel(STI_FLASHSS_MMC_CORE_CONFIG_1,
>>>> @@ -66,6 +70,8 @@ static void sti_mmc_core_config(struct udevice *dev)
>>>>         }
>>>>         writel(STI_FLASHSS_MMC_CORE_CONFIG4,
>>>>                host->ioaddr + FLASHSS_MMC_CORE_CONFIG_4);
>>>> +
>>>> +       return 0;
>>>>  }
>>>>
>>>>  static int sti_sdhci_probe(struct udevice *dev)
>>>> @@ -80,13 +86,20 @@ static int sti_sdhci_probe(struct udevice *dev)
>>>>          * MMC0 is wired to the SD slot,
>>>>          * MMC1 is wired on the high speed connector
>>>>          */
>>>> -
>>>> -       if (fdt_getprop(gd->fdt_blob, dev_of_offset(dev), "resets", NULL))
>>>> +       if (fdt_getprop(gd->fdt_blob, dev_of_offset(dev), "resets", NULL)) {
>>>>                 plat->instance = 1;
>>>> -       else
>>>> +               ret = reset_get_by_name(dev, "softreset", &plat->reset);
>>>
>>> Two questions:
>>>
>>> 1. The name "softreset" is in the "resets" property, isn't it? If so,
>>> can you use it instead of hard-coding "softreset" here?
>>
>> Sorry, i didn't understand what you mean by "can you use it instead of
>> hard-coding "softreset" here"
>
> I am wondering if the value of the 'resets' property is 'softtreset'?

"softreset" is the value of the "reset-names" property.

resets = <&softreset STIH407_MMC1_SOFTRESET>;
reset-names = "softreset";

But i am thinking to simplify this part.

Patrice

> If so, you could perhaps use that value instead of the string
> 'softreset'.
>
>>
>>
>>> 2. Can you not call reset_get_by_name() and deal with the error return
>>> (-ENOENT I think) if there is no such reset?
>>>
>>>> +               if (ret) {
>>>> +                       error("can't get reset for %s (%d)", dev->name, ret);
>>>> +                       return ret;
>>>> +               }
>>>> +       } else {
>>>>                 plat->instance = 0;
>>>> +       }
>>>>
>>>> -       sti_mmc_core_config(dev);
>>>> +       ret = sti_mmc_core_config(dev);
>>>> +       if (ret)
>>>> +               return ret;
>>>>
>>>>         host->quirks = SDHCI_QUIRK_WAIT_SEND_CMD |
>>>>                        SDHCI_QUIRK_32BIT_DMA_ADDR |
>>>> --
>>>> 1.9.1
>>>
>
> Regards,
> Simon
>